Prior art hot melt glue guns have been provided for feeding hot melt glue sticks into heating chamber in which the glue sticks are heated to melt temperatures, and then the melted, liquid glues are selectively dispensed from the glue guns. The glue guns usually have trigger assemblies which include gripper mechanisms for gripping the glue sticks and feeding the glue sticks to the heating chambers. The heating chambers which are usually heated by electrical resistance heaters, or other types of heating means. The heating chambers are typically cylindrical in shape and sized to have internal diameters which are approximately the sizes of the outer diameters of respective ones of the glue sticks such that walls which define the surfaces of the heating chambers fit against the peripheries of the glue sticks. The interior surfaces of the heating chamber walls are heated to temperatures for melting the solid glue sticks to form liquid glue. Heat is transferred by contact of the surface of the heating chamber walls with the peripheries of the glue sticks.
During use, hot glue guns are typically operated at periodic intervals to dispense the melted glues as required for use in assembly, and other types of fabrication and manufacturing operations. However, during the short periodic intervals when the melted glues are typically dispensed, operators dispense the glues at rates which is determined by the thermal transfer rates for heat to transfer from the heating elements, through the heating chamber walls and to the glue sticks. The melted glues are usually dispensed through flow nozzles which have restricted openings, requiring that the glues are fully melted prior to passing through the openings and from the hot glue guns. Thus, the times for manufacturing operations requiring the dispensing of hot melt glues are often longer than are desirable and which would be achievable if the melted glues could be dispensed at a faster rates.